When Derek Reads a Book
by SymphonicDeath
Summary: Derek "stumbles upon" Casey's diary and discovers her deepest fantasies.
1. Chapter 1

**A.N. **This was thought of because of my boyfriend. (Giggles and blushes manically.) Please read and review! :-)

Once upon a time, there was a lady called Nora, who fell in love with a man called George. Nora had two daughters – one called Lizzie, and the elder was called Casey. Meanwhile, George had three children – Marti, Edwin and Derek, the oldest. Nora and George got married and Nora's family moved into George's house. There, for two years the family lived harmoniously, with peace and tranquillity between all children.

Here we follow the story of the two older siblings, who, for the purposes of television clichés, are complete opposites and despise each other with every fibre of their being.

* * *

Derek opened one eye blearily and checked his alarm clock. The digits read 12.32pm. He rolled out of bed slowly, hitting his knee on the corner of his bed. _Way too early for a Saturday_, he thought grumpily. Carefully trying to avoid hitting other various pieces of furniture, he rubbed his eyes and groggily made his way the bathroom. Downstairs he could hear George trying to calm a screaming Marti down, and Casey yelling about her delicates being mixed in with Derek's dark clothes. He smirked. Casey was going out, and he was amused by the fact he could make her that little bit later.

After he had finished with his shower, he walked towards his room, and paused slightly towards Casey's room. It had often intrigued him what could be stashed away in there. Of course there were the usual books, clothes and girly crap, but what Derek wanted to see were the lacy underwear, dildos and erotic literature. Uninterested in any incestual implications, he searched opened her door. He thought with his penis – that's what God gave him one for, after all. Quite often Casey had yelled to him to "use his head once in a while", and he had to restrain himself from replying, "I always do."

He opened up her wardrobe first, pushing her tops and jeans to one side. He reached down to the bottom of her wardrobe. His eyes lit up when he found a stack of notepads, but his excitement lessened when he saw they were old school books. He then proceeded to attack her drawers, throwing aside her pink frilly tops, and sweaters in distaste. The raunchiest thing he could find was a thong with the words "Poke Me" written on. He messily stuffed everything back in the drawer. In disgust he moved to her bed, and looked underneath warily. Underneath Derek's bed were used tissues, crisps packets and pen caps. Underneath Casey's bed was...nothing.

Ready to give up and deem Casey as a prude for the rest of her life, he sat on her bed. With a stroke of brilliance he jumped up and turned towards her bed, lifting up her mattress. He found a single small black notebook. Slightly disappointed, he picked it up. Putting the mattress back down, he sat back on her bed and turned to the first page.

"_Oh Gods, he's back in my mind again". _Derek rolled his eyes at the first line. He continued reading.

"_Every time I look at him, I can't help imagining what it would be like to rip off his shirt and kiss his chest. I've always had a strange fascination to bite a guy's nipples, and tease it gently with my tongue." _ Derek laughed. _Now THIS is more like it._

"_Every time I see him in those faded blue jeans, I've often wondered how big he is. I can't imagine him ever being small; after all, he must have a reason for being a ladies' man. It's certainly not his intelligence! I wonder what it's like to kiss him. Every night, I can't help but imagine the way he'd lay on top of me, spreading my legs around me, and forcing himself into me."_

Derek couldn't believe he'd just read that. Eager to read more, he turned the page.

"DEREK! DINNER'S READY!" cried Nora from downstairs. He swore and flicked through the book, desperate to find out who this mystery man was. As he turned through the pages, a few words leaped out at him, notably "harder", "faster", "fuck" and "me". Casey had decorated the back page with hearts and stars. But as symmetrical as every heart was, as geometrically perfect every star was drawn, Derek could only see one thing.

The name inside the biggest heart was Derek.

* * *

Casey had gone out for the day with Emily, and was to return much later that evening. After taking his food to his room, and picked at it, his mind was racing. The first thing he processed was the fact his step sister had sexual thoughts about him. The second thing he processed with that his name was written in a heart. A HEART. Unless Casey had really messed up her symbolism, Derek was pretty sure she had more than step-sisterly feeling towards him. He decided to ignore those notions, and concentrated on the more important things at stake: the sexual fantasies.

Tempted to sneak back into her room and read more, George had called him downstairs to help him with some jobs in the garden. Derek protested that he had a fair bit of reading to do. Unsurprisingly, George didn't believe him, explaining to Derek that the importance of being a man is to prioritise one's responsibilities. Derek had to smile at this. _Oh, Casey knows I'm a man._

By the time it had reached 7pm, George had finally let Derek go. He was drenched in sweat and needed to take another shower. _Wish Casey could see me now._ Now, some readers may be thinking Derek's obsessive thoughts towards Casey are a clear sign of affection. But what many readers tend to forget is that Derek, at the age of 17, is hornier than a goat on steroids. And finding out that a non-blood-related step-sister was ready to do it with him in his back car was more than enough for Derek to act upon. Though the matter needed to be approached carefully. Living in the same house may prove some difficulties, especially as soon as Casey realises he was acting purely on his gender.

Derek waited in his room, waiting for Casey to return home. _God. I really need to get a life._

The digits on his clock read 8.00pm, and sure enough, he heard the front the door open. After greeting Nora, George and the kids, Casey came up the stairs. Derek heard her door closed. Casey always took showers in the morning; she wouldn't be refreshed and tired otherwise. Something she'd always nagged Derek about. Waiting a few more minutes, he left his room and knocked on the door.

"Who is it?"

"Derek. I need to talk to you about something important."

"Oh... come in."

Derek entered her room. Casey immediately noticed the expression on his face, which was deadly serious.

"Derek? Are you okay?"

Derek looked at her in amusement, and walked towards her. She was still in her pleated skirt and light blue shirt, sat on her bed. Derek gazed into her eyes.

"Casey..." he said softly. She shuddered. There was something about the way he was speaking, and the glint in his eyes, that didn't seem quite right.

"You see that chair over there?" he asked, pointing to her computer chair.

"Yes?" Casey answered nervously. Derek walked to closer to her, until he was touching her bed.

"I want to sit on that chair, and pull your body close to mine, wrapping your legs firmly around my waist. I'm going to rub my crotch into yours, as I pull you closer. I'm going to kiss your neck, slowly rubbing my tongue all over it, nibbling and sucking at your collarbone. I'm going to pull your crotch closer to mine as I suck your neck repeatedly, moving my tongue around and around." With every sentence he spoke, he moved on the bed, closer to Casey, until his face was inches away from hers. She was flushing, and half-dazed, as if waiting for him to continue. He obliged.

"I'm going to pick you up and throw you on the bed. I'm going to spread your legs, lay on top of you, and slowly unbutton your shirts, each button at a time." He paused, looking pointedly at her shirt. "As I'm unbuttoning your shirt, I'm going to rub my crotch into yours, faster and faster as each button is undone." With this, he moved his hands to the side of her waist and held them there. She held her breath.

"Then I'm going to throw your open shirt on the floor, revealing your bra. I'm slowly going to reach downwards, running my hand down your belly button, towards your thighs. I'll slowly move my hand around, inching at the edge of your tights." Casey's breathing was progressively getting louder, as she started to writhe slightly. Derek smirked. "I take my tongue, and take it all the way down from your neck to your belly button, kissing around the area, until I run my tongue down the top of your skirt. I slowly pull down your tights, inching away, revealing your smooth legs underneath. As one hand slowly pulls off the tights, the other hand moves around your back, softly stroking and feeling the bottom of your back, groping downwards, feeling everything in its path. The tights are off, I throw them on the floor, as I lay back on top of you, your legs spread wide."

Casey's hands were wandering towards Derek's trousers, but he held onto them, and pinned her to the bed. "So," he continued, growling into her ear. "You're now left with your skirt and your bra, as I slowly run my tongue around the inside your thighs. So Case?" he murmured into her ear. "I'm laying on top of you now, the things I could to you now." Cased tensed up, then Derek said the winning sentence: "I want to be inside of you."

With Casey moaning slightly in his ear, he continued, "I'd love to rub you up and down, and slowly move on your body. I want to take advantage of you – on the chair, the wall, the floor and the bed. I want to suck on your perfect nipples whilst being inside of you. I'm going to make you moan. I can't wait for your heels to dig into my back, whilst I'm moving in and out, deeper and deeper. I'll be moving faster and faster, until you're about to cum. And then do you know what I'm going to do next Case?"

"What?" she breathed, her eyes half closed.

"I'm going to my room now. Good night!" And with that, he jumped off her bed, and left her room.


	2. Chapter 2

**A.N. **Thanks for the great reviews, guys. :-) Reviews feed me. Forget nuts – I want reviews! (I wasn't talking about guys' nuts... honest.)

Casey lay on her bed, in complete awe. She took a deep breath, trying to calm herself down. She tried to comprehend what had just happened. Was Derek sexually attracted to her? Or better still, did he return her feelings towards him? She frowned – surely she was never _that_ obvious with her feelings.

She started to undress, and went to her drawers to find her pyjamas. Her clothes were completely messy, and her "Poke me" thong was lying on top.

_Oh – my – God._

She rushed towards her bed and lifted up the mattress. As she expected, the book was in a different place, the indent from its usual place marked clearly on the bottom of her mattress. Trying in vain not to hyperventilate, she opened up to the front page. There, she saw one small brown hair that definitely wasn't hers.

Now Casey was not a girl to be walked all over. Nor was she the type of girl to cry hysterically into her pillow, if she knew she could fix a problem. And boy, she was going to try. She marched out of her room, and stopped by his door, hearing loud thumping music coming from his bedroom. She paused, and thought about things logically. Derek wasn't much of a reader, and no doubt would he care very little about Casey's feelings. It was more than likely he just read the first page (_Or page 17_, Casey thought, blushing) and decided to act on it in impulse.

Deciding she'd just go to bed and happily ignore Derek for the rest of the month, she hid her diary in an old laptop case.

The next morning, Derek woke up, even more tired than he could ever remember. He'd set his alarm to 8.00am, the same time Casey woke up, just to aggravate her that little bit more. _Surely those precious few hours of her seeing my face would be a treat to her, if anything!_

Derek smiled, relishing last night's events in his mind. Oh, he knew she would've had sex with him, that's for sure. But it would have been a one-night stand, and where's the fun in that? He wanted Casey literally beg for it, beg in the way she'd come to him every night.

After taking a cold shower, he dressed in a pair of shorts and socks. He ran down the steps and stopped when he saw Casey stabbing at a piece of sausage.

"Good morning sister dearest," he said brightly, before she turned to look at him. Instead of Casey blushing and staring at his chest – which was the reaction he was hoping for – she frowned at him and continued eating her breakfast in silence.

"Derek, for God's sake, put a shirt on!" snapped George.

"What?" He held his hands up in protest. "Casey prances round in those miniskirts, or _belts,_ rather."

"Oh shut up Derek, no one needs to hear your pathetic excuses."

"Case, what's wrong with what I'm wearing? Speak up if there is a problem." He cupped his hand to his left ear and looked at Casey mockingly.

"You are a complete and utter retard."

"Oh!" Derek clutched a hand to her heart in mock agony. "That really breaks me y'know."

"Derek, shut the hell up and just DON'T talk to me for the rest of the day. In fact, make it a month."

"Casey!" Nora said, "That's not the nicest way to treat your step-brother."

Casey's mouth opened in shock. "Mom – Derek read my diary!"

George frowned. "Is this true Derek?"

"It most certainly is not. I would never _dream_ of reading my step-sister's boring diary."

"Liar!" Casey protested, looking at her mother for help.

Nora frowned at Derek. "Now Derek, please can you tell us all the truth? Invasion of privacy will not be tolerated in this house."

Derek smiled coolly. "I have not read Casey's diary. Unless Casey, you have direct proof that I have?" He smiled sweetly at her.

Casey was completely pissed off. After giving a cry of anguish, she stormed out of the kitchen.

"Better go and see what she wants," Derek said innocently to his parents. He ran up the stairs and followed her into her room.

"Casey." Derek swept imperiously into the office and planted himself directly in front of Casey's desk.

Casey was sorting out some clothes. "Get out."

He shrugged and held his hands out. "Why so snappy today? Yesterday you didn't seem to mind my company." Her eyes flashed dangerously at him, but she didn't reply. She spread out a black pair of jeans and red shirt on her bed.

"Derek, get out, I need to get ready."

"For what?"

"I have a date."

"With who?" he asked incredulously.

"Sam," she replied, not bothering to correct his grammar.

"MY Sam?" Derek asked, staring at her.

She turned away from her bed to look at him. "Yes," she said sweetly. "He called me up yesterday and asked if I'd like to spend the day with him."

"And you _agreed_?"

She frowned. "Yes I did. I'm not you; I don't go out with someone for three weeks then ignore them for life."

"Hey now, isn't that a little bit harsh-"

"And another thing," she snapped, cutting him off. "Don't ever come in my room without knocking." She walked towards him and pushed him out of the door roughly.

* * *

"I'm so glad to get away from that madhouse," Casey said smiling, as she walked with Sam through the mall.

"Derek problems?" Sam asked. He couldn't ever recall Casey's other siblings to be a pain in the ass.

"You know it." She stopped by an ice cream vendor. "Two vanillas please", she requested, paying the man. She handed one cone to Sam. She smiled. "Vanilla ice cream always helps me feel better after a fight with Derek." The pair sat down on a nearby bench.

"So, what did you two fight about?" ask Sam, expecting Casey to talk about Derek adding green dye to her shampoo or another similar situation. Instead, to Sam's surprise she blushed.

"Sam? Why did you ask me out today?"

He was taken aback. "Um... well we haven't spent much time together in a while, and I thought it would be great to catch up." Casey smiled. _He really is a nice guy._

"You really are different from Derek," she commented.

"What do you mean?"

"Well, Derek forgets about the previous girls he's dated as soon as a new one comes along. But you and I are still friendly together."

Sam shrugs. "I guess he doesn't need reminders of girls that mean nothing to him after a while."

"Nothing? Surely that's a bit harsh."

Sam shook his head. "Not really. When you think about the girls he dates, they're all as shallow as he appears to be. But he knows all of them aren't going to be around for long, so no point getting attached, right?"

"Yes... but how does he know they aren't the right girl for him within three weeks?"

"I think he actually knows on the first date, but he considers three weeks a fair amount of time to assess them. The girls he goes for are boring inside and uninterested in anything he likes."

"So why doesn't he look for a different type of girl?"

"He hasn't found her yet."

"Oh," she said. They remained sitting quietly, until Sam broke the silence.

"You've been talking a lot about Derek."

"Ah well, I kind of have to live with the guy."

"So, why _did_ you and Derek have a fight?" he asked, grinning at her.

She sighed. "Can you keep a secret?" she asked.

"Of course I can." He held out a hand and she shook it.

"Well, it's a long story..."

* * *

Casey walked through the front door, rather happy at the way the day panned out. She was relieved to have told at least one person. Even Emily didn't know. Sam took it incredibly well, and promised to keep her secret safe.

Casey's smile was wiped away when she saw Derek lip-locking with a blonde girl on the couch. Despite what Sam said about the girl being old news within a matter of weeks, she still couldn't help thinking he was a huge man-slut.

She slammed the door shut. Derek looked up. "Ahh, Casey," he said, grinning. "This is Amber. Amber, this is Casey, my step-sister". He drew out the word "sister".

Casey forced a smile. "Hi. Nice to meet you."

"Oh, Derek's never mentioned he had a step-sister!" Amber flashed a smile at Casey, her blonde streaks looking hideous against her orange top.

"Probably doesn't want to ruin any of his credibility," she said sarcastically, before glaring at Derek and storming upstairs, for the second time that day.

Derek watched her go up the stairs, and mentally cursed himself. He had spent all day looking for her diary, and out of frustration, rang up a random girl he barely knew from their school, in another attempt to infuriate Casey.

**A.N. **Hope you enjoy. I know it's more dialogue than action - but trust me, the action will come soon enough. ;-)


	3. Chapter 3

As Casey expected, her mattress was slightly crooked, and her wardrobe was half open. She grinned at the laptop case, right next to her desk. At least she could infuriate Derek, though very slightly, it was enough.

Downstairs Derek was making excuses to Amber.

"Listen... it's getting late, and there's school tomorrow! You better go." He stood up quickly.

"But Derek," she purred, wrapping an arm around his neck, "It's only 8 o' clock."

He scratched his head. "Homework?" he trailed off pathetically.

"Oh Derek, I didn't think you'd be the type to care about homework," she grinned at him.

_Her hair looks hideous. _Amber grabbed the back of his head and planted a kiss on him. Just at that moment Casey had come downstairs to make up with Derek. Her eyes widened at the sight of what only could be described as "sucking face". She grimaced and stormed back upstairs. Derek didn't notice.

Casey ignored Derek the next morning. Even when he had offered to give her a lift, she walked straight past him to Emily's house. He sighed. _At least I have Amber_, he thought, rolling his eyes.

* * *

"Hey Derek!" said Sam, running up to him smiling.

Derek glared into his locker, avoiding Sam's gaze. "Don't 'Hey Derek' me. Why did you take out Casey yesterday?"

Sam was slightly stunned. "To catch up with her?"

Derek snorted. "You don't take out an ex-girlfriend just to "catch up with them". Thinking of winning Casey back?"

"No Derek. I really was just catching up with her. I _can_ be friends with a girl, unlike you."

"Meaning?" Derek raised an eyebrow.

"Amber?"

"Hey – how do you know –" Derek was interrupted by said 'girlfriend' plunging into his arms and planting a kiss on his mouth.

Now Sam snorted and started laughing. "It's kind of spread across the school now."

"WHAT?!"

"Aww, what's wrong snookie?" Amber pinched his cheeks and smiled at him.

"Nothing," he replied through gritted teeth.

The bell rang. "Well..." said Derek, desperate to leave Amber and his snickering best friend. "I better get to class."

* * *

Derek walked into his English class, the events of the weekend still plaguing his mind.

"Right," said Mrs. Kingston, tidying up papers on her desk. "Today we're going to discuss 'creative writing'."

The next hour passed by like a blur. At the mention of 'homework', Derek stirred out of his stupor. "Now class, for your assignment I want you to write a letter. The letter will be for someone you admire or care about. You will be credited for originality and figurative language."

Derek groaned.

* * *

The next evening, Derek sat by his desk, ready to begin. Normally he'd be out practising hockey with Sam and the rest of his team, but George gave him an ultimatum due to his failing grades: get better grades, or quit the hockey team.

Derek stared dumbly at a blank sheet of paper. "_Who do I care about?"_ His first thoughts was George, but writing about how much he loved his father for leaving Derek on his own in the house to throw random parties wasn't particularly endearing. His thoughts drifted to Casey, and he smirked, wondering if he could even manage more than a line.

"_Dearest Casey,_" he first wrote, deciding it was rather patronising.

"_It has come to my recent attention that you are rather enamoured by me._" _No,_ he thought, tipp-exing it out. _That's a LITTLE big-headed, even for me._

"_Shall I compare thee to a summer's day?_" he wrote, and snickered. It was proving difficult to be serious. Then he imagined Casey naked, and that seemed to do the trick.

"_Casey, Casey, Casey, Case. I remember the first day I met you. Two years ago. That skinny, gawky –" _He erased "skinny and gawky". "_That over-achiever, grade-grubbing 15-year old. The most popular girl in your school. But that all changed when you came here, didn't it? Suddenly you found that _I, _Derek Venturi, am the most popular person in school, and you weren't. Not even close. But through the two years, I've seen how you grown up into the woman you are now._" Derek paused slightly.

"_That beautiful young woman that any girl would die to be, that any guy would die to be WITH. And above all those guys, I am the one who desires you the most. Not just for what is underneath those ridiculous thongs you wear but for YOU, the person I've fallen in love with. The girl who hits me every time I take too long in the shower, the girl who yells my name in a voice high enough to kill bats on a daily basis, the girl I wish I could cuddle and fall asleep with every day._

_They have been many times I've just wanted to grab you and kiss you for hours. It pains me how I can't hold your hand when we're out shopping, or for me to put my arms around your waist. And about all those other girls I've dated? Why do you think I drop them in three weeks? It's because they _

_aren't you. NO ONE can ever compare to you, and I was a fool to think I could move on. You're beautiful, simply the most stunning girl I've ever seen. Those other girls are plastic fakes – you are not sexy, not "hot", but simply "beautiful". You were always far too good for Sam and Max._

"_Casey, I love you. Love you more than any girl I have ever known. Love you more than any girl I HAVE ever loved. I want to spend the rest of my life with you. I want to lay down with you on a grassy meadow, and look at the stars. I want to hold hands on the beach with you, the hot sand tickling our feet. I want YOU to be mine, Case, because no other girl is as perfect as you are to me."_

Slightly stunned he could pen so much in so little time, considering he took 5 hours to write a 500 hundred word essay for History, he folded up the piece of paper, and placed it on top of his desk. He quickly drafted an essay about how much Sam meant to him, and shoved it into his school bag.

* * *

"Derek, give me the damn spoon!"

"Ooh, talking to me now are you?" he replied, snatching the spoon out of Casey's reach.

"Derek, stop teasing your sister," said Nora in a weary voice.

"_Step_-sister," Derek corrected. He obediently gave Casey back her spoon, and she flounced to the living room, eating her yoghurt.

"What are you doing?" he demanded, as Casey was sat in _his _chair. She could abuse him all she wanted, but sitting in his was crossing the line. In fact, if the line was in China, she was in Chile.

She looked at him and smiled sweetly. "I'm just sitting here, watching TV."

Derek tutted. "Casey, I'm not sure if you're aware of the rules of this house yet, but that is MY chair. No one sits in it, but me."

She raised an eyebrow. "I'm not moving."

"I'll give you one more chance. Get out, or I'll make you."

"Go on then," she challenged, looking him straight in the eye. Summoning up enough courage, he strode over to Casey. Unsure which part of her body was appropriate to touch, he settled for her legs. Grabbing her calves with both hands, he began pulling Casey of his chair. She shrieked and starting kicking him, pushing him away with one hand, and hitting him with one hand, desperately trying to hold on to her yoghurt with the other.

Derek then grabbed her hips trying to pull her off from there, whilst resting his knees on her legs so she wouldn't kick him. Casey remained resistant. He tickled her sides. She shrieked, and her arms flailed, causing the yoghurt to fly out of her hand and land neatly on Derek's head,

She burst out laughing, and finally it was Derek who stormed up the stairs.

_Stupid little know-it-all._

He stuck his head under the shower nozzle and washed off the yoghurt lumps. His t-shirt was sodden. And Derek did NOT like being unnecessarily wet. He gritted his teeth and stormed into Casey's room, determined to find her diary.

He re-checked her wardrobe, cupboards and under her mattress. He checked her school bag and book section. _What's a ridiculously obviously place that I wouldn't dream of checking? _He climbed on Casey and looked at the top of the wardrobe. Nothing. He then spied her old laptop case next to her desk and eagerly ran up to it. Inside was the familiar black book.

"Hello, old friend" he said fondly, flipping to the back page. It was dated to yesterday's date.

"_Weird day today._

"_I told Sam everything. Even what happened between Derek and I yesterday. He didn't freak out like I expected to, in fact he seemed quite understanding. Despite my reasoning of 'but he's my step-brother!' didn't faze him; Sam just saw it was bound to happened. _

"_Does EVERYONE see it or something? What's with this 'bound to happen' nonsense? Was it inevitable I would fall in love with my step-brother? The most annoying and infuriating person I have ever met in my life, yet I can't get him out of head. Every day, my life is based around him. I wake up and think about him, think about what time he goes to the bathroom in the morning, time myself so I never cross paths when he or I are in our towels, going to our rooms. I made the mistake of leaving my diary in such an obvious place, and he read it all. _

"_Saturday night was simultaneously the worst and best night of my life. God I wish it could have gone further, but then what? He'd just have his way with me then ignore my existence for the rest of my life? I don't he'd realise I'd be pouring out my soul to him in every one of my kisses, giving myself to him out of love, not just lust. Unlike that Amber bitch. I can just relish in the fact she won't last more than two weeks. Actually, one week._

"_Gods, I love him. Yes, I admit it. I'm in love with my step-brother. I'm too tired and fed up to write anymore."_

As Derek stared at the book, stunned, Casey walked into the room, clutching the letter he had placed on his desk.

**AN. **Yay for cliff-hangers!


End file.
